1 /*
2 * Copyright (c) 2001, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_RUNTIME_PERFDATA_HPP
26 #define SHARE_RUNTIME_PERFDATA_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/atomic.hpp"
30 #include "runtime/perfDataTypes.hpp"
31 #include "runtime/perfMemory.hpp"
32 #include "runtime/timer.hpp"
33
34 template <typename T> class GrowableArray;
35
36 /* jvmstat global and subsystem counter name space - enumeration value
37 * serve as an index into the PerfDataManager::_name_space[] array
38 * containing the corresponding name space string. Only the top level
39 * subsystem name spaces are represented here.
40 */
41 enum CounterNS {
42 // top level name spaces
43 JAVA_NS,
44 COM_NS,
45 SUN_NS,
46 // subsystem name spaces
47 JAVA_GC, // Garbage Collection name spaces
48 COM_GC,
49 SUN_GC,
50 JAVA_CI, // Compiler name spaces
51 COM_CI,
52 SUN_CI,
53 JAVA_CLS, // Class Loader name spaces
54 COM_CLS,
55 SUN_CLS,
56 JAVA_RT, // Runtime name spaces
57 COM_RT,
58 SUN_RT,
59 JAVA_OS, // Operating System name spaces
60 COM_OS,
61 SUN_OS,
62 JAVA_THREADS, // Threads System name spaces
63 COM_THREADS,
64 SUN_THREADS,
65 JAVA_THREADS_CPUTIME, // Thread CPU time name spaces
66 COM_THREADS_CPUTIME,
67 SUN_THREADS_CPUTIME,
68 JAVA_PROPERTY, // Java Property name spaces
69 COM_PROPERTY,
70 SUN_PROPERTY,
71 NULL_NS,
72 COUNTERNS_LAST = NULL_NS
73 };
74
75 /*
76 * Classes to support access to production performance data
77 *
78 * The PerfData class structure is provided for creation, access, and update
79 * of performance data (a.k.a. instrumentation) in a specific memory region
80 * which is possibly accessible as shared memory. Although not explicitly
81 * prevented from doing so, developers should not use the values returned
82 * by accessor methods to make algorithmic decisions as they are potentially
83 * extracted from a shared memory region. Although any shared memory region
84 * created is with appropriate access restrictions, allowing read-write access
85 * only to the principal that created the JVM, it is believed that the
86 * shared memory region facilitates an easier attack path than attacks
87 * launched through mechanisms such as /proc. For this reason, it is
88 * recommended that data returned by PerfData accessor methods be used
89 * cautiously.
90 *
91 * There are three variability classifications of performance data
92 * Constants - value is written to the PerfData memory once, on creation
93 * Variables - value is modifiable, with no particular restrictions
94 * Counters - value is monotonically changing (increasing or decreasing)
95 *
96 * The performance data items can also have various types. The class
97 * hierarchy and the structure of the memory region are designed to
98 * accommodate new types as they are needed. Types are specified in
99 * terms of Java basic types, which accommodates client applications
100 * written in the Java programming language. The class hierarchy is:
101 *
102 * - PerfData (Abstract)
103 * - PerfLong (Abstract)
104 * - PerfLongConstant (alias: PerfConstant)
105 * - PerfLongVariant (Abstract)
106 * - PerfLongVariable (alias: PerfVariable)
107 * - PerfLongCounter (alias: PerfCounter)
108 *
109 * - PerfByteArray (Abstract)
110 * - PerfString (Abstract)
111 * - PerfStringVariable
112 * - PerfStringConstant
113 *
114 *
115 * As seen in the class hierarchy, the initially supported types are:
116 *
117 * Long - performance data holds a Java long type
118 * ByteArray - performance data holds an array of Java bytes
119 * used for holding C++ char arrays.
120 *
121 * The String type is derived from the ByteArray type.
122 *
123 * A PerfData subtype is not required to provide an implementation for
124 * each variability classification. For example, the String type provides
125 * Variable and Constant variability classifications in the PerfStringVariable
126 * and PerfStringConstant classes, but does not provide a counter type.
127 *
128 * Performance data are also described by a unit of measure. Units allow
129 * client applications to make reasonable decisions on how to treat
130 * performance data generically, preventing the need to hard-code the
131 * specifics of a particular data item in client applications. The current
132 * set of units are:
133 *
134 * None - the data has no units of measure
135 * Bytes - data is measured in bytes
136 * Ticks - data is measured in clock ticks
137 * Events - data is measured in events. For example,
138 * the number of garbage collection events or the
139 * number of methods compiled.
140 * String - data is not numerical. For example,
141 * the java command line options
142 * Hertz - data is a frequency
143 *
144 * The performance counters also provide a support attribute, indicating
145 * the stability of the counter as a programmatic interface. The support
146 * level is also implied by the name space in which the counter is created.
147 * The counter name space support conventions follow the Java package, class,
148 * and property support conventions:
149 *
150 * java.* - stable, supported interface
151 * com.sun.* - unstable, supported interface
152 * sun.* - unstable, unsupported interface
153 *
154 * In the above context, unstable is a measure of the interface support
155 * level, not the implementation stability level.
156 *
157 * Currently, instances of PerfData subtypes are considered to have
158 * a life time equal to that of the VM and are managed by the
159 * PerfDataManager class. All constructors for the PerfData class and
160 * its subtypes have protected constructors. Creation of PerfData
161 * instances is performed by invoking various create methods on the
162 * PerfDataManager class. Users should not attempt to delete these
163 * instances as the PerfDataManager class expects to perform deletion
164 * operations on exit of the VM.
165 *
166 * Examples:
167 *
168 * Creating performance counter that holds a monotonically increasing
169 * long data value with units specified in U_Bytes in the "java.gc.*"
170 * name space.
171 *
172 * PerfLongCounter* foo_counter;
173 *
174 * foo_counter = PerfDataManager::create_long_counter(JAVA_GC, "foo",
175 * PerfData::U_Bytes,
176 * optionalInitialValue,
177 * CHECK);
178 * foo_counter->inc();
179 *
180 * Creating a performance counter that holds a variably change long
181 * data value with units specified in U_Bytes in the "com.sun.ci
182 * name space.
183 *
184 * PerfLongVariable* bar_variable;
185 * bar_variable = PerfDataManager::create_long_variable(COM_CI, "bar",
186 .* PerfData::U_Bytes,
187 * optionalInitialValue,
188 * CHECK);
189 *
190 * bar_variable->inc();
191 * bar_variable->set_value(0);
192 *
193 * Creating a performance counter that holds a constant string value in
194 * the "sun.cls.*" name space.
195 *
196 * PerfDataManager::create_string_constant(SUN_CLS, "foo", string, CHECK);
197 *
198 * Although the create_string_constant() factory method returns a pointer
199 * to the PerfStringConstant object, it can safely be ignored. Developers
200 * are not encouraged to access the string constant's value via this
201 * pointer at this time due to security concerns.
202 *
203 * Creating a performance counter in an arbitrary name space that holds a
204 * value that is sampled by the StatSampler periodic task.
205 *
206 * PerfDataManager::create_counter("foo.sampled", PerfData::U_Events,
207 * &my_jlong, CHECK);
208 *
209 * In this example, the PerfData pointer can be ignored as the caller
210 * is relying on the StatSampler PeriodicTask to sample the given
211 * address at a regular interval. The interval is defined by the
212 * PerfDataSamplingInterval global variable, and is applied on
213 * a system wide basis, not on an per-counter basis.
214 *
215 * Creating a performance counter in an arbitrary name space that utilizes
216 * a helper object to return a value to the StatSampler via the take_sample()
217 * method.
218 *
219 * class MyTimeSampler : public PerfLongSampleHelper {
220 * public:
221 * jlong take_sample() { return os::elapsed_counter(); }
222 * };
223 *
224 * PerfDataManager::create_counter(SUN_RT, "helped",
225 * PerfData::U_Ticks,
226 * new MyTimeSampler(), CHECK);
227 *
228 * In this example, a subtype of PerfLongSampleHelper is instantiated
229 * and its take_sample() method is overridden to perform whatever
230 * operation is necessary to generate the data sample. This method
231 * will be called by the StatSampler at a regular interval, defined
232 * by the PerfDataSamplingInterval global variable.
233 *
234 * As before, PerfSampleHelper is an alias for PerfLongSampleHelper.
235 *
236 * For additional uses of PerfData subtypes, see the utility classes
237 * PerfTraceTime and PerfTraceTimedEvent below.
238 *
239 * Always-on non-sampled counters can be created independent of
240 * the UsePerfData flag. Counters will be created on the c-heap
241 * if UsePerfData is false.
242 *
243 * Until further notice, all PerfData objects should be created and
244 * manipulated within a guarded block. The guard variable is
245 * UsePerfData, a product flag set to true by default. This flag may
246 * be removed from the product in the future.
247 *
248 * There are possible shutdown races between counter uses and counter
249 * destruction code. Normal shutdown happens with taking VM_Exit safepoint
250 * operation, so in the vast majority of uses this is not an issue. On the
251 * paths where a concurrent access can still happen when VM is at safepoint,
252 * use the following pattern to coordinate with shutdown:
253 *
254 * {
255 * GlobalCounter::CriticalSection cs(Thread::current());
256 * if (PerfDataManager::has_PerfData()) {
257 * <update-counter>
258 * }
259 * }
260 */
261 class PerfData : public CHeapObj<mtInternal> {
262
263 friend class StatSampler; // for access to protected void sample()
264 friend class PerfDataManager; // for access to protected destructor
265 friend class VMStructs;
266
267 public:
268
269 // the Variability enum must be kept in synchronization with the
270 // the com.sun.hotspot.perfdata.Variability class
271 enum Variability {
272 V_Constant = 1,
273 V_Monotonic = 2,
274 V_Variable = 3,
275 V_last = V_Variable
276 };
277
278 // the Units enum must be kept in synchronization with the
279 // the com.sun.hotspot.perfdata.Units class
280 enum Units {
281 U_None = 1,
282 U_Bytes = 2,
283 U_Ticks = 3,
284 U_Events = 4,
285 U_String = 5,
286 U_Hertz = 6,
287 U_Last = U_Hertz
288 };
289
290 // Miscellaneous flags
291 enum Flags {
292 F_None = 0x0,
293 F_Supported = 0x1 // interface is supported - java.* and com.sun.*
294 };
295
296 private:
297 char* _name;
298 Variability _v;
299 Units _u;
300 bool _on_c_heap;
301 Flags _flags;
302
303 PerfDataEntry* _pdep;
304
305 protected:
306
307 void *_valuep;
308
309 PerfData(CounterNS ns, const char* name, Units u, Variability v);
310 virtual ~PerfData();
311
312 // create the entry for the PerfData item in the PerfData memory region.
313 // this region is maintained separately from the PerfData objects to
314 // facilitate its use by external processes.
315 void create_entry(BasicType dtype, size_t dsize, size_t dlen = 0);
316
317 // sample the data item given at creation time and write its value
318 // into the its corresponding PerfMemory location.
319 virtual void sample() = 0;
320
321 public:
322
323 // returns a boolean indicating the validity of this object.
324 // the object is valid if and only if memory in PerfMemory
325 // region was successfully allocated.
326 inline bool is_valid() { return _valuep != nullptr; }
327
328 // returns a boolean indicating whether the underlying object
329 // was allocated in the PerfMemory region or on the C heap.
330 inline bool is_on_c_heap() { return _on_c_heap; }
331
332 // returns a pointer to a char* containing the name of the item.
333 // The pointer returned is the pointer to a copy of the name
334 // passed to the constructor, not the pointer to the name in the
335 // PerfData memory region. This redundancy is maintained for
336 // security reasons as the PerfMemory region may be in shared
337 // memory.
338 const char* name() const { return _name; }
339 bool name_equals(const char* name) const;
340
341 // returns the variability classification associated with this item
342 Variability variability() { return _v; }
343
344 // returns the units associated with this item.
345 Units units() { return _u; }
346
347 // returns the flags associated with this item.
348 Flags flags() { return _flags; }
349
350 // returns the address of the data portion of the item in the
351 // PerfData memory region.
352 inline void* get_address() { return _valuep; }
353 };
354
355 /*
356 * PerfLongSampleHelper, and its alias PerfSamplerHelper, is a base class
357 * for helper classes that rely upon the StatSampler periodic task to
358 * invoke the take_sample() method and write the value returned to its
359 * appropriate location in the PerfData memory region.
360 */
361 class PerfLongSampleHelper : public CHeapObj<mtInternal> {
362 public:
363 virtual jlong take_sample() = 0;
364 };
365
366 /*
367 * PerfLong is the base class for the various Long PerfData subtypes.
368 * it contains implementation details that are common among its derived
369 * types.
370 */
371 class PerfLong : public PerfData {
372
373 protected:
374
375 PerfLong(CounterNS ns, const char* namep, Units u, Variability v);
376
377 public:
378 // returns the value of the data portion of the item in the
379 // PerfData memory region.
380 inline jlong get_value() { return *(jlong*)_valuep; }
381 };
382
383 /*
384 * The PerfLongConstant class, and its alias PerfConstant, implement
385 * a PerfData subtype that holds a jlong data value that is set upon
386 * creation of an instance of this class. This class provides no
387 * methods for changing the data value stored in PerfData memory region.
388 */
389 class PerfLongConstant : public PerfLong {
390
391 friend class PerfDataManager; // for access to protected constructor
392
393 private:
394 // hide sample() - no need to sample constants
395 void sample() { }
396
397 protected:
398
399 PerfLongConstant(CounterNS ns, const char* namep, Units u,
400 jlong initial_value=0)
401 : PerfLong(ns, namep, u, V_Constant) {
402
403 if (is_valid()) *(jlong*)_valuep = initial_value;
404 }
405 };
406
407 /*
408 * The PerfLongVariant class, and its alias PerfVariant, implement
409 * a PerfData subtype that holds a jlong data value that can be modified
410 * in an unrestricted manner. This class provides the implementation details
411 * for common functionality among its derived types.
412 */
413 class PerfLongVariant : public PerfLong {
414
415 protected:
416 PerfLongSampleHelper* _sample_helper;
417
418 PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
419 jlong initial_value=0)
420 : PerfLong(ns, namep, u, v) {
421 if (is_valid()) *(jlong*)_valuep = initial_value;
422 }
423
424 PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
425 PerfLongSampleHelper* sample_helper);
426
427 void sample();
428
429 public:
430 inline void inc() { (*(jlong*)_valuep)++; }
431 inline void inc(jlong val) { (*(jlong*)_valuep) += val; }
432 inline void dec(jlong val) { inc(-val); }
433 inline void reset() { (*(jlong*)_valuep) = 0; }
434 };
435
436 /*
437 * The PerfLongCounter class, and its alias PerfCounter, implement
438 * a PerfData subtype that holds a jlong data value that can (should)
439 * be modified in a monotonic manner. The inc(jlong) and add(jlong)
440 * methods can be passed negative values to implement a monotonically
441 * decreasing value. However, we rely upon the programmer to honor
442 * the notion that this counter always moves in the same direction -
443 * either increasing or decreasing.
444 */
445 class PerfLongCounter : public PerfLongVariant {
446
447 friend class PerfDataManager; // for access to protected constructor
448
449 protected:
450
451 PerfLongCounter(CounterNS ns, const char* namep, Units u,
452 jlong initial_value=0)
453 : PerfLongVariant(ns, namep, u, V_Monotonic,
454 initial_value) { }
455
456 PerfLongCounter(CounterNS ns, const char* namep, Units u,
457 PerfLongSampleHelper* sample_helper)
458 : PerfLongVariant(ns, namep, u, V_Monotonic,
459 sample_helper) { }
460 };
461
462 /*
463 * The PerfLongVariable class, and its alias PerfVariable, implement
464 * a PerfData subtype that holds a jlong data value that can
465 * be modified in an unrestricted manner.
466 */
467 class PerfLongVariable : public PerfLongVariant {
468
469 friend class PerfDataManager; // for access to protected constructor
470
471 protected:
472
473 PerfLongVariable(CounterNS ns, const char* namep, Units u,
474 jlong initial_value=0)
475 : PerfLongVariant(ns, namep, u, V_Variable,
476 initial_value) { }
477
478 PerfLongVariable(CounterNS ns, const char* namep, Units u,
479 PerfLongSampleHelper* sample_helper)
480 : PerfLongVariant(ns, namep, u, V_Variable,
481 sample_helper) { }
482
483 public:
484 inline void set_value(jlong val) { (*(jlong*)_valuep) = val; }
485 };
486
487 /*
488 * The PerfByteArray provides a PerfData subtype that allows the creation
489 * of a contiguous region of the PerfData memory region for storing a vector
490 * of bytes. This class is currently intended to be a base class for
491 * the PerfString class, and cannot be instantiated directly.
492 */
493 class PerfByteArray : public PerfData {
494
495 protected:
496 jint _length;
497
498 PerfByteArray(CounterNS ns, const char* namep, Units u, Variability v,
499 jint length);
500 };
501
502 class PerfString : public PerfByteArray {
503
504 protected:
505
506 void set_string(const char* s2);
507
508 PerfString(CounterNS ns, const char* namep, Variability v, jint length,
509 const char* initial_value)
510 : PerfByteArray(ns, namep, U_String, v, length) {
511 if (is_valid()) set_string(initial_value);
512 }
513
514 };
515
516 /*
517 * The PerfStringConstant class provides a PerfData sub class that
518 * allows a null terminated string of single byte characters to be
519 * stored in the PerfData memory region.
520 */
521 class PerfStringConstant : public PerfString {
522
523 friend class PerfDataManager; // for access to protected constructor
524
525 private:
526
527 // hide sample() - no need to sample constants
528 void sample() { }
529
530 protected:
531
532 // Restrict string constant lengths to be <= PerfMaxStringConstLength.
533 // This prevents long string constants, as can occur with very
534 // long classpaths or java command lines, from consuming too much
535 // PerfData memory.
536 PerfStringConstant(CounterNS ns, const char* namep,
537 const char* initial_value);
538 };
539
540 /*
541 * The PerfStringVariable class provides a PerfData sub class that
542 * allows a null terminated string of single byte character data
543 * to be stored in PerfData memory region. The string value can be reset
544 * after initialization. If the string value is >= max_length, then
545 * it will be truncated to max_length characters. The copied string
546 * is always null terminated.
547 */
548 class PerfStringVariable : public PerfString {
549
550 friend class PerfDataManager; // for access to protected constructor
551
552 protected:
553
554 // sampling of string variables are not yet supported
555 void sample() { }
556
557 PerfStringVariable(CounterNS ns, const char* namep, jint max_length,
558 const char* initial_value)
559 : PerfString(ns, namep, V_Variable, max_length+1,
560 initial_value) { }
561
562 public:
563 inline void set_value(const char* val) { set_string(val); }
564 };
565
566
567 /*
568 * The PerfDataList class is a container class for managing lists
569 * of PerfData items. The intention of this class is to allow for
570 * alternative implementations for management of list of PerfData
571 * items without impacting the code that uses the lists.
572 *
573 * The initial implementation is based upon GrowableArray. Searches
574 * on GrowableArray types is linear in nature and this may become
575 * a performance issue for creation of PerfData items, particularly
576 * from Java code where a test for existence is implemented as a
577 * search over all existing PerfData items.
578 *
579 * The abstraction is not complete. A more general container class
580 * would provide an Iterator abstraction that could be used to
581 * traverse the lists. This implementation still relies upon integer
582 * iterators and the at(int index) method. However, the GrowableArray
583 * is not directly visible outside this class and can be replaced by
584 * some other implementation, as long as that implementation provides
585 * a mechanism to iterate over the container by index.
586 */
587 class PerfDataList : public CHeapObj<mtInternal> {
588
589 private:
590
591 // GrowableArray implementation
592 typedef GrowableArray<PerfData*> PerfDataArray;
593
594 PerfDataArray* _set;
595
596 // method to search for a instrumentation object by name
597 static bool by_name(const char* name, PerfData* pd);
598
599 protected:
600 // we expose the implementation here to facilitate the clone
601 // method.
602 PerfDataArray* get_impl() { return _set; }
603
604 public:
605
606 // create a PerfDataList with the given initial length
607 PerfDataList(int length);
608
609 // create a PerfDataList as a shallow copy of the given PerfDataList
610 PerfDataList(PerfDataList* p);
611
612 ~PerfDataList();
613
614 // return the PerfData item indicated by name,
615 // or null if it doesn't exist.
616 PerfData* find_by_name(const char* name);
617
618 // return true if a PerfData item with the name specified in the
619 // argument exists, otherwise return false.
620 bool contains(const char* name) { return find_by_name(name) != nullptr; }
621
622 // return the number of PerfData items in this list
623 inline int length();
624
625 // add a PerfData item to this list
626 inline void append(PerfData *p);
627
628 // create a new PerfDataList from this list. The new list is
629 // a shallow copy of the original list and care should be taken
630 // with respect to delete operations on the elements of the list
631 // as the are likely in use by another copy of the list.
632 PerfDataList* clone();
633
634 // for backward compatibility with GrowableArray - need to implement
635 // some form of iterator to provide a cleaner abstraction for
636 // iteration over the container.
637 inline PerfData* at(int index);
638 };
639
640 class PerfTickCounters : public CHeapObj<mtInternal> {
641 private:
642 const char* _name;
643 PerfCounter* const _elapsed_counter;
644 PerfCounter* const _thread_counter;
645 public:
646 PerfTickCounters(const char* name, PerfCounter* elapsed_counter, PerfCounter* thread_counter) :
647 _name(name), _elapsed_counter(elapsed_counter), _thread_counter(thread_counter) {
648 }
649
650 const char* name() { return _name; }
651
652 PerfCounter* elapsed_counter() const {
653 return _elapsed_counter;
654 }
655 long elapsed_counter_value() const {
656 return _elapsed_counter->get_value();
657 }
658 inline jlong elapsed_counter_value_ms() const;
659 inline jlong elapsed_counter_value_us() const;
660
661 PerfCounter* thread_counter() const {
662 return _thread_counter;
663 }
664 jlong thread_counter_value() const {
665 return _thread_counter->get_value();
666 }
667 inline jlong thread_counter_value_ms() const;
668 inline jlong thread_counter_value_us() const;
669
670 void reset() {
671 _elapsed_counter->reset();
672 _thread_counter->reset();
673 }
674 };
675
676 /*
677 * The PerfDataManager class is responsible for creating PerfData
678 * subtypes via a set a factory methods and for managing lists
679 * of the various PerfData types.
680 */
681 class PerfDataManager : AllStatic {
682
683 friend class StatSampler; // for access to protected PerfDataList methods
684
685 private:
686 static PerfDataList* _all;
687 static PerfDataList* _sampled;
688 static PerfDataList* _constants;
689 static const char* _name_spaces[];
690 static volatile bool _has_PerfData;
691
692 // add a PerfData item to the list(s) of know PerfData objects
693 static void add_item(PerfData* p, bool sampled);
694
695 protected:
696
697 // return the list of all known PerfData items that are to be
698 // sampled by the StatSampler.
699 static PerfDataList* sampled();
700
701 public:
702
703 // method to check for the existence of a PerfData item with
704 // the given name.
705 static inline bool exists(const char* name);
706
707 // method to map a CounterNS enumeration to a namespace string
708 static const char* ns_to_string(CounterNS ns) {
709 return _name_spaces[ns];
710 }
711
712 // methods to test the interface stability of a given counter namespace
713 //
714 static bool is_stable_supported(CounterNS ns) {
715 return (ns != NULL_NS) && ((ns % 3) == JAVA_NS);
716 }
717 static bool is_unstable_supported(CounterNS ns) {
718 return (ns != NULL_NS) && ((ns % 3) == COM_NS);
719 }
720
721 // methods to test the interface stability of a given counter name
722 //
723 static bool is_stable_supported(const char* name) {
724 const char* javadot = "java.";
725 return strncmp(name, javadot, strlen(javadot)) == 0;
726 }
727 static bool is_unstable_supported(const char* name) {
728 const char* comdot = "com.sun.";
729 return strncmp(name, comdot, strlen(comdot)) == 0;
730 }
731
732 // method to construct counter name strings in a given name space.
733 // The string object is allocated from the Resource Area and calls
734 // to this method must be made within a ResourceMark.
735 //
736 static char* counter_name(const char* name_space, const char* name);
737
738 // method to construct name space strings in a given name space.
739 // The string object is allocated from the Resource Area and calls
740 // to this method must be made within a ResourceMark.
741 //
742 static char* name_space(const char* name_space, const char* sub_space) {
743 return counter_name(name_space, sub_space);
744 }
745
746 // same as above, but appends the instance number to the name space
747 //
748 static char* name_space(const char* name_space, const char* sub_space,
749 int instance);
750 static char* name_space(const char* name_space, int instance);
751
752
753 // these methods provide the general interface for creating
754 // performance data resources. The types of performance data
755 // resources can be extended by adding additional create<type>
756 // methods.
757
758 // Constant Types
759 static PerfStringConstant* create_string_constant(CounterNS ns,
760 const char* name,
761 const char *s, TRAPS);
762
763 static PerfLongConstant* create_long_constant(CounterNS ns,
764 const char* name,
765 PerfData::Units u,
766 jlong val, TRAPS);
767
768
769 // Variable Types
770 static PerfStringVariable* create_string_variable(CounterNS ns,
771 const char* name,
772 int max_length,
773 const char *s, TRAPS);
774
775 static PerfLongVariable* create_long_variable(CounterNS ns,
776 const char* name,
777 PerfData::Units u,
778 jlong ival, TRAPS);
779
780 static PerfLongVariable* create_long_variable(CounterNS ns,
781 const char* name,
782 PerfData::Units u, TRAPS) {
783 return create_long_variable(ns, name, u, (jlong)0, THREAD);
784 };
785
786 static PerfLongVariable* create_long_variable(CounterNS ns,
787 const char* name,
788 PerfData::Units u,
789 PerfLongSampleHelper* sh,
790 TRAPS);
791
792
793 // Counter Types
794 static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
795 PerfData::Units u,
796 jlong ival, TRAPS);
797
798 static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
799 PerfData::Units u,
800 PerfLongSampleHelper* sh,
801 TRAPS);
802
803
804 // these creation methods are provided for ease of use. These allow
805 // Long performance data types to be created with a shorthand syntax.
806
807 static PerfConstant* create_constant(CounterNS ns, const char* name,
808 PerfData::Units u, jlong val, TRAPS) {
809 return create_long_constant(ns, name, u, val, THREAD);
810 }
811
812 static PerfVariable* create_variable(CounterNS ns, const char* name,
813 PerfData::Units u, jlong ival, TRAPS) {
814 return create_long_variable(ns, name, u, ival, THREAD);
815 }
816
817 static PerfVariable* create_variable(CounterNS ns, const char* name,
818 PerfData::Units u, TRAPS) {
819 return create_long_variable(ns, name, u, (jlong)0, THREAD);
820 }
821
822 static PerfVariable* create_variable(CounterNS ns, const char* name,
823 PerfData::Units u,
824 PerfSampleHelper* sh, TRAPS) {
825 return create_long_variable(ns, name, u, sh, THREAD);
826 }
827
828 static PerfCounter* create_counter(CounterNS ns, const char* name,
829 PerfData::Units u, TRAPS) {
830 return create_long_counter(ns, name, u, (jlong)0, THREAD);
831 }
832
833 static PerfCounter* create_counter(CounterNS ns, const char* name,
834 PerfData::Units u,
835 PerfSampleHelper* sh, TRAPS) {
836 return create_long_counter(ns, name, u, sh, THREAD);
837 }
838
839 static PerfTickCounters* create_tick_counters(CounterNS ns,
840 const char* counter_name,
841 const char* elapsed_counter_name,
842 const char* thread_counter_name,
843 PerfData::Units u, TRAPS) {
844 PerfCounter* elapsed_counter = create_long_counter(ns, elapsed_counter_name, u, (jlong)0, THREAD);
845 PerfCounter* thread_counter = create_long_counter(ns, thread_counter_name, u, (jlong)0, THREAD);
846
847 PerfTickCounters* counters = new PerfTickCounters(counter_name, elapsed_counter, thread_counter);
848 return counters;
849 }
850
851 static void destroy();
852 static bool has_PerfData() { return Atomic::load_acquire(&_has_PerfData); }
853 };
854
855 // Useful macros to create the performance counters
856 #define NEWPERFTICKCOUNTER(counter, counter_ns, counter_name) \
857 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
858 PerfData::U_Ticks,CHECK);}
859
860 #define NEWPERFEVENTCOUNTER(counter, counter_ns, counter_name) \
861 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
862 PerfData::U_Events,CHECK);}
863
864 #define NEWPERFBYTECOUNTER(counter, counter_ns, counter_name) \
865 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
866 PerfData::U_Bytes,CHECK);}
867
868 #define NEWPERFTICKCOUNTERS(counter, counter_ns, counter_name) \
869 {counter = PerfDataManager::create_tick_counters(counter_ns, counter_name, counter_name "_elapsed_time", \
870 counter_name "_thread_time", PerfData::U_Ticks,CHECK);}
871
872 // Utility Classes
873
874 /* PerfTraceElapsedTime and PerfTraceThreadTime will administer a PerfCounter used as a time accumulator
875 * for a basic block much like the TraceTime class.
876 * PerfTraceElapsedTime uses elapsedTimer to measure time which reflects the elapsed time,
877 * and PerfTraceThreadTime uses ThreadTimer which reflects thread cpu time.
878 *
879 * Example:
880 *
881 * static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, 0LL, CHECK);
882 *
883 * {
884 * PerfTraceElapsedTime ptt(my_time_counter);
885 * // perform the operation you want to measure
886 * }
887 *
888 * Note: use of this class does not need to occur within a guarded
889 * block. The UsePerfData guard is used with the implementation
890 * of this class.
891 */
892
893 class PerfTraceTimeBase : public StackObj {
894 friend class PerfPauseTimer;
895 private:
896 BaseTimer* _t;
897 protected:
898 PerfLongCounter* _counter;
899
900 public:
901 inline PerfTraceTimeBase(BaseTimer* t, PerfLongCounter* counter) : _t(t), _counter(counter) {}
902
903 ~PerfTraceTimeBase();
904
905 jlong active_ticks() { return _t->active_ticks(); }
906
907 const char* name() { return _counter->name(); }
908 BaseTimer* timer() { return _t; }
909 };
910
911 class PerfTraceElapsedTime: public PerfTraceTimeBase {
912 protected:
913 elapsedTimer _t;
914
915 public:
916 inline PerfTraceElapsedTime(PerfCounter* counter) : PerfTraceTimeBase(&_t, counter) {
917 if (!UsePerfData || counter == nullptr) { return; }
918 _t.start();
919 }
920 };
921
922 class PerfTraceThreadTime: public PerfTraceTimeBase {
923 protected:
924 ThreadTimer _t;
925
926 public:
927 inline PerfTraceThreadTime(PerfCounter* counter) : PerfTraceTimeBase(&_t, counter) {
928 if (!UsePerfData || !TraceThreadTime || counter == nullptr) { return; }
929 _t.start();
930 }
931 };
932
933 // PerfTraceTime is a utility class to provide the ability to measure both elapsed and thread cpu time using a single object.
934 class PerfTraceTime : public StackObj {
935 friend class PerfPauseTimer;
936 private:
937 PerfTickCounters* _counters;
938 PerfTraceElapsedTime _elapsed_timer;
939 PerfTraceThreadTime _thread_timer;
940
941 public:
942 inline PerfTraceTime(PerfTickCounters* counters, bool is_on = true):
943 _counters(counters),
944 _elapsed_timer(counters != nullptr ? counters->elapsed_counter() : nullptr),
945 _thread_timer(counters != nullptr ? counters->thread_counter() : nullptr) {}
946
947 const char* name() { return _counters->name(); }
948 PerfTraceTimeBase* elapsed_timer() { return &_elapsed_timer; }
949 PerfTraceTimeBase* thread_timer() { return &_thread_timer; }
950
951 jlong elapsed_timer_active_ticks() {
952 return _elapsed_timer.active_ticks();
953 }
954
955 jlong thread_timer_active_ticks() {
956 return _thread_timer.active_ticks();
957 }
958 };
959
960 class PerfPauseTimerBase : public StackObj {
961 protected:
962 bool _is_active;
963 BaseTimer* _timer;
964
965 public:
966 inline PerfPauseTimerBase(PerfTraceTimeBase* timer, bool is_on) : _is_active(false), _timer(nullptr) {
967 _is_active = (is_on && timer != nullptr);
968 if (UsePerfData && _is_active) {
969 _timer = timer->timer();
970 _timer->stop(); // pause
971 }
972 }
973
974 inline ~PerfPauseTimerBase() {
975 if (UsePerfData && _is_active) {
976 assert(_timer != nullptr, "");
977 _timer->start(); // resume
978 }
979 }
980 };
981
982 class PerfPauseTimer : public StackObj {
983 private:
984 PerfPauseTimerBase _elapsed_timer_pause;
985 PerfPauseTimerBase _thread_timer_pause;
986
987 public:
988 inline PerfPauseTimer(PerfTraceTime* timer, bool is_on) :
989 _elapsed_timer_pause(timer != nullptr ? timer->elapsed_timer() : nullptr, is_on),
990 _thread_timer_pause(timer != nullptr ? timer->thread_timer() : nullptr, is_on) {}
991 };
992
993 /* The PerfTraceElapsedTimeEvent class is responsible for counting the
994 * occurrence of some event and measuring the elapsed time of
995 * the event in two separate PerfCounter instances.
996 *
997 * Example:
998 *
999 * static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, CHECK);
1000 * static PerfCounter* my_event_counter = PerfDataManager::create_counter("my.event.counter", PerfData::U_Events, CHECK);
1001 *
1002 * {
1003 * PerfTraceElapsedTimeEvent ptte(my_time_counter, my_event_counter);
1004 * // perform the operation you want to count and measure
1005 * }
1006 *
1007 * Note: use of this class does not need to occur within a guarded
1008 * block. The UsePerfData guard is used with the implementation
1009 * of this class.
1010 *
1011 * Similarly, PerfTraceThreadTimeEvent can count the occurrence of some event and measure the thread cpu time of the event.
1012 * PerfTraceTimedEvent can count the occurrence of some event and measure both the elapsed time and the thread cpu time of the event.
1013 */
1014 class PerfTraceElapsedTimeEvent: public PerfTraceElapsedTime {
1015 protected:
1016 PerfLongCounter* _eventp;
1017
1018 public:
1019 inline PerfTraceElapsedTimeEvent(PerfCounter* counter, PerfLongCounter* eventp) : PerfTraceElapsedTime(counter), _eventp(eventp) {
1020 if (!UsePerfData || counter == nullptr) return;
1021 _eventp->inc();
1022 }
1023 };
1024
1025 class PerfTraceThreadTimeEvent: public PerfTraceThreadTime {
1026 protected:
1027 PerfLongCounter* _eventp;
1028
1029 public:
1030 inline PerfTraceThreadTimeEvent(PerfCounter* counter, PerfLongCounter* eventp) : PerfTraceThreadTime(counter), _eventp(eventp) {
1031 if (!UsePerfData || counter == nullptr) return;
1032 _eventp->inc();
1033 }
1034 };
1035
1036 class PerfTraceTimedEvent : public PerfTraceTime {
1037 protected:
1038 PerfLongCounter* _eventp;
1039
1040 public:
1041 inline PerfTraceTimedEvent(PerfTickCounters* counters, PerfLongCounter* eventp, bool is_on = true) : PerfTraceTime(counters, is_on), _eventp(eventp) {
1042 if (!UsePerfData || !is_on || counters == nullptr) return;
1043 _eventp->inc();
1044 }
1045 };
1046 #endif // SHARE_RUNTIME_PERFDATA_HPP